$ { {5} \times \left[\begin{array}{r}{0} \\ {2} \\ {4}\end{array}\right] = {?} } $
To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{r}{5}\times{0} \\ {5}\times{2} \\ {5}\times{4}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{r}{0} \\ {10} \\ {20}\end{array}\right]}$